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A common query I see across the internet is Ingersoll Rand air compressor won’t start under load. This article will provide you will all the possible reasons as to why your Ingersoll Rand air compressor won’t restart, along with existing reader questions and responses related to the issue.

To learn more about Ingersoll Rand air compressors, visit our brand page here!

Table of Contents

Reasons Ingersoll Rand Air Compressor Won’t Restart

If your Ingersoll Rand air compressor won’t restart after it fills the air tank, the check valve is likely stuck open causing the air compressor not start under load. The check valve’s role is to prevent tank air from back-flowing towards the pump. The stuck-open check valve will cause high pump head pressure, preventing the compressor from being able to restart.

Follow these steps to test the check valve:

  1. Shut off the compressor and pull the ring on the safety valve to bleed the air from the air tank until it’s empty.
  2. Turn on the compressor to fill the air tank.
  3. Bleed air out of the tank to reach the cut-in pressure, so the pressure switch attempts to restart the motor to refill the air tank.

If the compressor won’t start with air in the tank, replace the check valve.

If the check valve is not the issue, then it’s likely that it may be the unloader valve failing. To diagnose if the unloader valve is working properly, simply listen to the compressor closely as it reaches the cut-off pressure. Just after the compressor stops running you should be able to hear a short sharp discharge of air from the unloader valve, which is usually located on the pressure switch itself.

If you don’t hear the unloader valve releasing pressure, this could be the cause of your air compressor not restarting when there’s pressure in the tank. Visit our Air Compressor Won’t Start Under Load guide for information!

Other possibilities include the motor being too hot and the thermal overload switch not allowing the compressor to restart until it’s cooled down, or even a faulty/weak start capacitor that has the capability to initially start the compressor but not restart the compressor.

Additional Ingersoll Rand Pages

Reader Questions & Responses

Ingersoll Rand Air Compressor Will Not Restart – Ingersoll Rand Air Compressor Troubleshooting

Question

Ingersoll Rand 7.5 220 single-phase I replaced the pressure switch does the same thing.

Ingersoll Rand 7.5 HP compressor
New Ingersoll Rand T-30compressor

Response

Tony, turn off the compressor and open the tank drain to drain all the air out. Close the drain, and start the air compressor?

Does it start OK?

The reset button you refer to, is it on the electrical panel, motor, or on the breaker, or elsewhere?

Please post your response as a comment here so I can follow the thread.


Ingersoll Rand Air Compressor Won’t Restart Under Load – Ingersoll Rand Air Compressor Troubleshooting

Question

I am having an issue with my older 80 Gallon IR Compressor. The motor has been replaced with a Baldor 5HP Farm Duty Motor, drawing 28amps.

I have run 10 Romex Wire from my GE box to a 220 Outlet I installed in my garage. The total wire run from the box is about 35 ft, with another 10′ of 10 ga Rominex wired to a 220 plug directly on the new Condor Pressure Switch to the motor.

The breaker is a double pole GE 30 amp.

The compressor does not have an unloader.

The problem is when the compressor starts up, I get an initial 5-second hum, no spinning, and then the breaker trips. I’m wondering if I need a larger wire and a bigger breaker to cover the initial start-up of the motor. My question is, if the motor is pulling 28 amps, is that 14 per leg? If so, if the wire is brokered at 30 amps per leg, then the motor at start-up would have to be pulling over double is operating amperage in order to blow the breaker correct? That seems like an awful lot of start-up amps. I have rechecked all of my wirings from the fuse box, to the 220 outlets, the plug to the compressor, the pressure switch, and the wiring inside the motor, and everything is correct. The only thing I can think of is the amperage at startup exceeding the rating on the wire, but it shouldn’t.

Appreciate any advice you may have.

Thanks, Billy

Response

All motors pull more amps at startup or inrush.

The humming motor suggests to me that it’s either not getting enough amps or the start capacitor isn’t kicking in to boost the amps and get the motor running.

Can you do a capacitor check to see if it/they are working? See how to test the capacitors on this site. Leave us a comment to let us know what you found, K?

Bill


Ingersoll Rand Air Compressor Won’t Restart – Ingersoll Rand Air Compressor Troubleshooting

Question

The compressor is a Matco made by Ingersoll Rand .220 single phase. Replaced pressure switch that did not help.

Response

Tony, if you dump the air and plug the unit back in, will it start OK?

Will the Matco air compressor reach normal cut-out pressure and stop normally?

If it does, when it stops, do you see/hear the unloader valve operated?

Any answers as a comment here will help figure out what’s going on with your compressor.


Ingersoll Rand Air Compressor Won’t Start Under Load – Ingersoll Rand Air Compressor Troubleshooting

Question

The 5 hp compressor was bad when I was given the machine. I installed a 3 hp compressor on the 80-gallon tank from a different machine with a bad motor. So now the 5hp 230-volt single-phase motor runs the 3hp compressor.

When the tank is empty everything runs just fine – up to pressure and shuts off and I hear the unloader hiss off the head pressure.

Use the air and the motor kicks in and runs at what seems like 1/2 speed for 3 -4 seconds and trips the 20 amp 230-volt breakers.

Had the motor megged out and all looked okay. Had the Capacitor (760 – 840 milliohms) checked out and it looked okay. Run the motor by itself and all okay.

I emptied the tank again and had the same result. The motor does not even get hot when filling the tank.

I replaced the capacitor with a similar size (708 – 850) that was available and the motor kicked out after 3 seconds of 1/2 speedrunning.

Any ideas? Hook 2 capacitors in parallel together? Thanks

Response

Jim, it sounds like it could be a power supply issue to me. Any chance of that?

If the caps are OK, and the motor is fine, then what might trip it out is low power.


If you have any questions regarding Ingersoll Rand air compressors not restarting, please leave a comment below, with a photo if applicable, so that someone can help you!